Telephone-exchange signal system.



' atented Mar. 4,1902. W. S. PACA. TELEPHONE EXCHANGE SIGNAL SYSTEM.

(Application filed may 7. 1901.3

THE Norms Pzrsns'bo. vno'raumou WASHINGTON. o c.

UNITE STATES PATENT Gr mes.

YVI-LLIAM S. PAOA, OF ERIE, PENNSYLVANIA, ASSIGNOR OF ONE-HALF TO PETER I-I. ADAMS, OF ERIE, PENNSYLVANIA.

TELEPHONE-EXCHANGE SIGNAL SYSTEM.

SPECIFICATION forming part of Letters Patent No. 694,662, dated March 4, 1902.

Application filed May 7, 1901.

Serial a. 59,129. (No model.)

To all whom it may concern: I l A Be it known that I, WILLIAM S. PAGA, a citizen of the United States, residing at the city of Erie, in the countyot Erie and State of Pennsylvania, have invented certain new and useful Improvements in Telephone-Ere change SignalSystems; and I do hereby declare the following to be a full, clear, and exand to the letters of'reference marked thereon, forming part of this specification.

This invention relates to improvements in telephone-exchange signal systems, and has for its object the construction of exchange mechanism and telephone-circuits in such a manner that when a subscriber rings up the exchange and removes his receiver from the hook and the operator inserts an answeringplug'into the jack of the subscriber calling it operates to light an ,incandescenthsignalj lamp and when the subscriber called for removes his receiver from the hook it operates to light a second incandescent lamp to approximately half-glow'and at the same time reduces the first lamp lightedto half-glow, thereby indicating to the operator that the subscriber called for has answered, and both of said lampsv remain at such half-glow until the party calling and the party called for both hang their receivers upon theirhooks, which operates to extinguish both lamps. Thus theoperator can at all times know when the party called for has answered and when both parties have finished their conversation withoutlistening or verbally asking the parties whether they have finished their conversation. r

The features of this invention, the con: struction of the mechanism, and the arrange ment of the circuits therein are hereinafter set forth and described, and illustrated in the accompanying drawing, in which the figure is a diagrammatic drawing of an exchange.

mechanism and two subscribers mechanisms embodying this invention.

In this drawing two subscribers stations are shown and distinguished as stations No.

l and No. 2, and A A are main-line circuits leading from station No. l to a drop B anda jack 0 on the exchange-switchboard, and D D main-line circuits leading from station No. 2 tea drop B and a jack '0 on'the switchboard, and E E are respectively operators answer and call plugs connected by the usual flexible cords ff and e 6 with the usual-operators switch F and through this-switch to the operators telephone E and office-gener- 6o ator E The lines ff, leadingfrom the answering-plugs, also connect directly through a relay H and thence by wire it to a battery B and ground G. The answer and call'plugs Eand E are used interchangeably in the jacks O and 0, according to the station calling the exchange. The apparatus at each of the subscribers stations consists of a magnetogenerator I, bell magnets I, a transmitter J, a battery'B, an induction-coil J, a receiver K, and a hook-switch lever 7c of the usual construction. Inwiring up the'circuits of this apparatus, however, a ground G is provided, from which a wire 9 extends to a battery B and thence 'by wire g to wire h o. Now following the wire it it connects with the relay H and thence by wires f f and branches f and f to repeating-coil M M and opera tors switch F, and by continuation of lines f f to contacts 6 e on answering switch-plug E, and thence, when the plug E isinserted into jack 0 by jack-bodyciand jack-tongue c, to main lines A A and by branch lines b" b to drop-magnet B, and by continuation of the lines A AVby wires a a to bell-mag- 8 nets-l and by line'7c leading from the wire joining the windings of the coils 0f the bell- 'magnet at a point approximately midway ground G, with the bell-,magnet coils in this manner is for the purpose of' utilizing ithe'impedance of the bell-magnet coils and maintaining a perfect electrical balance of the circuit and to prevent the ground Gr operating to produce induction and cross-talk on the circuit. This ground-circuit operates to draw the armature II of the relay H downward and close a switch-contact h, which 'operates to close a circuit with a battery B through a wire I, lamp L, wire Z, contact h, wire I contacts 7L2, and wire I", which operates to light the lamp L to a full glow, thus indicating the use of the callers telephone. The operator then turns the portion F of the switch F as indicated in dotted lines, connecting her telephone in circuit, and finds out the station the caller desires to be connected with. She then inserts the call-plug E into the jack 0 connected with the subscriber called for, which in the drawing is designated as station No. 2. The operator then turns the part F of the switch F, as shown in dotted lines therein, so as to connect the lines 6 and c with the branch lines 6 and c leading to the oflice-generator, (not shown,) and rings up the subscriber called for in the usual manner, after which the parts F F of the switch F are returned to their normal positions, as indicated in full lines therein, and when the party called for removes his receiver K from the hook 7s a circuit is formed from the ground G by wire g, battery B, and wire g to wire 7L 0, and by wire 0 to and through relay 0, and thence by lines at and m to wires m m and by branches m and m to repeating-coil M M, and by continuation of lines m and m through the part F of switch F, and by wires 6 and e to contacts 6 and e on the call-plug E, and thence when the plug E is inserted in the jack 0 by jackbody 0 and jack-tongue c to main lines D D, and by branch lines I) b to drop-magnet B, and by continuation of lines D D by wires a a tobell-magnets I and line K to switchcontact k, operated by the heel of the switchlever when the receiver K is removed therefrom, and thence by line k to ground G. The stations No. 1 and No. 2 are identical in their construction and arrangement of their circuits. Thiscircuit then operates to draw the armature O of the relay 0 downward, thereby operating the switch 0 which closes the contacts R S and 77,3 and simultaneously breaks the contact 7L2. This brings a lamp L into circuit, and the circuit from the bat tery B divides and passes into both lamps L and L by wires 1 Z I, contact 7L3, and wires Z Z and I, but only lights and maintains the lamps L and L at half-glow, which indicates to the operator that the lines from station No. 1 and No. 2 are connected and in use. The mechanism being in this position, the talkingcircuit between stations Nos. 1 and 2, commencing at station No.1, is by linespp, main lines A A, thence through jack-body c and jack-tonguec of jack 0 to contacts 9 c on plug E, thence by linesff and branchesf f to the part F of the operators switch F, thence by lines randsto contactsRS,and thencebylines m and m to part F of the operators switch F, and thence by wires (2 e to contacts 6 and e on plug E, and thence by jack-bodyc and jacktongue 0 of jack 0, by main lines DD and lines 1) p, to receiver K at station No. 2, and vice versa. This gives a direct'talking-circuit without utilizing a repeating-coil M M;&

but in case the operator switches in during a conversation and breaks the direct circuit at F of the switch F'the conversation can be continued through the repeating-coil M M, and the same result is obtained in case of any derangement of the switch O and the contacts R and S. It will be observed that while the lines a connect with the lines 17, forming one side of the talking-circuit, and thence through wire a bell-coils I, line 70 contact 70, and line 70 with ground G, yet the bellcoils I, being wound with a resistance of approximately six hundred ohms, operate as impedance-coils and eltectually prevent the passage of the high alternating voice-currents therethrough.

When the parties at two stationsfor exam ple, stations No. 1 and No. 2-arecon'nected, as hereinbefore described,should either party hang up his receiver K on the hook it the operation of the relays H and 0 will not in any wise be interfered with; but if both receivers K are returned to their hooks 70 then the relays H and O are cut out of circuit, and the circuits leading to the lamps L and L being broken by the retraction of the armatures H and O are extinguished, thus clearly indicating to the operator that the parties connected have closed their conversation; but if the party at one of the stations connected-401' example, the party at station No. 2should hang up his receiver and the party at station No. 1 should leave the station and fail to're turn his receiver to the hook 7c and after a time the operator should desire to find out whether the parties were still using the line she can. move the portion F of the switch F so as to break the direct connection between relay H and relay 0, and thence by battery B and ground G, thus releasing relay 0 and cutting-out lamp L and causing lamp L to rise to full glow, thus indicating that the receiver at station No. 1 was not upon the hook K, and Vice Versa, if the receiver was oil of the hook at station No. 2, the relay 11 would be released, cutting out lamp L'and causing lamp L to rise to full glow, thus in either case indicating which party had neglected to hang up his receiver, and if before the operator withdraws the plugs E and E the party at station No. l desires another connection he removes his receiver K from the hook 7;, cansing the lamp L to become lighted to fullglow; but it, on the other hand, the party at station No. 2 desires to call before the plugs E E have been withdrawn and removes'his receiver K from the hook 70' both of the lamps L and L will be lighted to ahalf-glow. Thus the operator can readily know which of the stations desires another call and can thus arrange the answer and call plugs E and E to respond thereto and call the party desired, as hereinbefore described.

I have thus shown diagrammatically and described an apparatus embodyingtwo subscribers stations and an exchange'mechanism embodying my invention. It-is obvious,

however, that the jacks, answer and call plugs, and other portions of the exchange ap paratus will be increased in number many times in the construction and operation of'a telephone exchange system, to correspond with the number of subscribers connected therewith. It is also: obvious that many changes and modifications-can be made in the construction and arrangement of the parts of the apparatus herein shown and described without departing from the spirit of my invention; therefore What'I claim as new, and-desire to secure by Letters Patent of the United States, is 1. In a telephone-exchange signal system, an exchange apparatus substantially comprising a battery, a lamp in circuit therewith, a relay for closing and openingsaid lamp-circuit, a battery connected with said relay and with a ground, and cord-circuits from said relay to a switch-plug, and a subscribers-telephone-station apparatus, a wire leading from between the bell-magnets of said station apparatus, and a switch adapted to connect said wire witha ground, substantially as set forth. 2. In a telephone-exchange signal system, an exchange apparatus substantially com prising a battery, lamps in circuits therewith, relays for closing and opening said lamp-circuits, a battery connected with said relays and with ground, a circuit'leading from one relay to a repeating-coil, an operators switch and telephone and to an answering-plug, a circuit leading from another relay to a repeating-coil, an operators switch and to a call-plug, subscribersQtelephone-station apparatus, a wire leading from the-bell-magnets of the station apparatus, a switch in the station apparatus adapted .to connect said Wire with ground-wires, and wires connecting said subscribers-station apparatus with drop and jack mechanism on the exchangeswitchboard, substantially'as set forth.

3. In a telephone-exchange signal system, a switchboard substantially comprising jacks and drop mechanism, an operators switch, a call :apparatus, a repeating-coil, a battery, lamps in circuit therewith, relays operating switches for closing and opening said lampcircuits, a battery connected with the relays and with a ground, wires leading from the relays to the repeating-coil,the operators switch and thence by branches to an operators telephone and a calling apparatus, and continuations of said wires leading to answering and calling plugs adapted to operate in the jacks on said switchboard, subscribers-telephonestation apparatus, wires leading from the bellmagnets of the station apparatus, switches in the station apparatus adapted to connect said wires with ground-wires, and Wires connecting said subscribers stations with drop and jack mechanism on the exchange-switchboard, substantially as set forth.

4. In atelephone-exchange signal system, a switchboard, jacks, connecting-plugs, an

operators switch, a relay, switches operated by said relay, line-circuits from the connecting-plugs to the operators switch and thence to the switches operated by the relay, and

operators switch, and thence to the switch] operated by the relay, and branch circuits from said circuits connecting withthe repeating-coil, substantially as set forth. p

6. In a telephone-exchange signal system, a switchboard substantially comprising jack and drop mechanism, switch-plugs operating in said jacks, an operators switch, an operators telephone, a call apparatus, a repeatingcoil, switches, a relay for operating the same, circuits leading from the switch-plugs to the operators switch and thence to the switch operated by the relay, branchcircuits from said circuits connecting-with the repeatingcoil, a battery, signal-lamps in circuit therewith, relays operating to open and close said lamp-circuits, a battery for operating said-relays, and circuits from said relays to the switch-plugs, substantially asset forth.

'7. In a telephone-exchange signal system, a switchboard substantially comprising jack, switch plug and drop mechanism, main-line circuits from subscribers telephone-stations connecting with said jacks and drop mechan ism, an operators switch, an operatorstelephone, a call apparatus, a repeating-coil, a battery, lamps 'in circuit therewith, relays for closing and opening said lamp circuits,

line-circuits from said switch-plugs tosaid relays, a switch in one of said line-"circuits operated by one of said relays, abattery grounded at one side andconnected with said relays on the other side, subscribers-station apparatus connected with the main-line circuits leading to the jacks on the switchboard,a wire leading from the bell-magnets of each subscribers station apparatus to a" switch therein adapted to connect such wire to ground, substantially as set forth.

8. In a telephone-exchange signal system, a switchboard, jacks, switch-plugs, an oper ators switch, a repeating-coil, relays,switches operated thereby, circuits leadin gfrom switch plugs through the operators switch to one of the relays and to the switches operated thereby, and branches leading from said circuits to the repeating-coil, circuits leading from the other switch-pings t0 the other relay, and branches leading from said circuits to the 0pcrators switch and to the repeating-coil, and a battery and ground connected with said rclnys, substantially as set forth.

In testimony whereof I afiix my signature in presence of two witnesses.

XVILLIAM S. PACA.

\Vitnesses:

H. M. STURGEON, FRANK A. BLILEY. 

